Slat drier for drying paper



Patented May 'l 1923,

Jonnwnnnnn vnnnnn, orwoncnsrnn, MASSACHUSETTS.

' p sLn'r `narnia ronnnYINe rnrnn.

Appiieatiqn mea June 23, 1921, 'serial No. 479,871.

T a?? whom. t may concern.' f

vBe it known thatl, JOHN VARBEN Yun-' Dnn, a citizen of the United States, andv a resident 'of Worcester, Massachusetts, have inventedl new anduseful Improvements in Slat y'Driers for Drying Paper, which inventio-n is fully set forth in the following specification. A I

This invention relates tofwhat are known as slat driers which are cylinders or drums formed at their periphery of longitudinally extending wooden 'slats or bars spaced equi-1 distant around the `drum andrv over which the paper to be dried is led. `Such driers are used principally 'for drying paper to which size `has been applied, the paper being lled successively over a series` or batteryof. driers sufficient in number to attain the de-A sired, drying. They arel also adapted for useJ in drying vpaper to which other liquids are* applied such as acid liquids for parchmentizing paper, etc.

course of manufacture-thereof is to pass it oversuitably heated 'hollow cast iro-n drlers, drums, or cylinders'. llortheproduction of some grades or characterl of paper it ispled from said cast iron driers through a bath of sizing liquid and v.then through avv-size press whichsqueezesout superfluous liquid picked upin the b-ath. The paper must then be again dried, but such second drying cannot be satisfactorily performed for the production of a high quality of paper by use of the aforesaid cast iron driers because the drying action thereof would be too severe at'this stage of the production and thev size would not,

be caused to thoroughly penetrate the sheet. Hence, such second drying is usually accomplished in one" of three ways, that is, first, the paper isrolled upV and carried to a festooning system where it is dried, such step and its mechanism, and the handling of the paper which it involves, being separatev from and therefore not bearing the relationship of continuity to the continuoussystems of mechanisms which have operated in thepro-y duction of the paper upto that p oint; or

second, the paper after leaving the size press is cut in sheets and hung up to dry in which lis known asa dry-loft, just as a woman would hang up clothes to d ry, such method and the" handling of the paper wh1ch 1t 1nvolves also being non-continuous in its relz'i'tionship to the operations which have preceded it; or,"third, the paper is ledifrom the. Y 'l size press over a series or battery pf slat driers. VSuch drying by the use of slat dri-` f ers, although as' yet employed onlyjin. a fewf mills, is rapidly increasing infavor, forthe reasons, amongst others, that lit is much more economical than the Aother methods, may be joined onto thelother mechanisms or operatlons a's'part of a continuous system, and yieldsj'any entirely 1 satisfactory product. 65 ln slat driers or drums heretofore used `or proposed for use in drying sized paper, provision has been madev for agitating and cir f culating air within the drum and'in contact with the paper thereon by theuSe 'of' rotat- `707 ingjfan blades,asv shown, for example, in patent'to Kilberry, dated October 31. 1916, No. `1,203,010. ,Ore `object attained by the g fpresentl ,invention is the introduction'ofair or other suitable drying medium at the/cem ter of the space within the drum bythe use f ,y of a hollow orvtubularsupporting shaft 'for rlhe usual method of drying paper in the said-relative rotation has been provided be- Y 'i' tween the supportingshaft on the one'hand, and the slats or Slat-carrying parts ordrum v on the other hand, with the result that/the driving power communicated to such drumat one end must be transmitted throughout the drum tothe other end thereof through the medium ofthefsla'tsj'and -their end fas- 90 tenings to thedrum heads to wh-ichthey are secured at opposite ends. `Such method of driving throughlthe slats imposes undue stra-in upon and Yloo-sensthe connections of the slats, imposes strain upon theslats themselves likely' to vproduce warping? thereof, and altogether-results in a structure'likely togive trouble from thevery beginning of'.

its use andpractically unusable with heavy papers.y 'Another object attained by the 100 present invention is the provision of'a struc-i f ture inv which the driving'strain or torque is transmitted from end tofend ofthe drum'V by a rigid central shaft' forming'a direct and rigid part ofthe drum structure and substantially, and preferably entirely relieving the slatsof strain in that connection; f And a still further object 'attained by this, invention'is the useV ofa tubular shaftboth vas the means for delivering suitable drying able.v source of power.

medium within the drum and as the rigid and rotating shaft of thef drier or drum through which driving power is transmitted to the relief of strain upon the slats andl their connections; Still. other' 'objects attained will be apparent from, the accompanying drawing illustrativeof what l now believe to be preferred embodiments of the invention, and wherein- Fig. 1 is a longitudinal vertical section of one embodiment; y j Y Y Fig 2 is an end elevation with the shaft in ,section on line 2`2 of Fig. 1;

Fig. 3 is a longitudinal vertical section of a modified structure; and

F ig. 4 is an endv elevation Vwith the shaft in section on line 4 4 of Fig. 3l

VReferringt'o F igs. v1 and 2, 5 is a tubular shaft rotatably supported in bearings 6 and 7, the frame work upon which said bearings are mounted notbeing shown. 8 is a pulley keyed; on shaft and adapted to be driven by asuitable belt, not shown, fromany suit- 9 is a pipe for delivering air, or other suitable drying medium, preferably heated, and under pressure or not as desired, from any suitable source of'l supply to. one end of the tubular shaft 5 whichis closed at its other endby a plug 10 and has perforations 11 through its wall for radially discharging the. dryingVv medium within the drum and into' contact with a web of paper passing thereover. Between the end of fixed pipe 9 and the open end of rotatable shaft l5 there are shown parts constituting a joint of the general type disclosed in my Patent No. 1,180,806, of April 25, 1916, said parts including a stationary abutment 12 mounted on pipe 9, a tubular memberul threaded onto the end of shaft 5 and flangedv at its righthand end to form an enlarged flat end bearing surface; a nonrotating supporting member 14 about part 13; and a floating packing orjoint member 15 interposedbetween and in' Contact at oppositer sides respectively with the rotating surface of part 13 and the non-rotating concave bearing surface of abutment l12, said relatively rotating surfaces being lubricated from lubricant reservoirs through suitable passages as'shown. 16 and 17 are two similar drum heads or'enjds of' wheel-like construction and having radiating spokes 18,a

shaft so as to rotate therewith, and the driving power is applied directly to the shaft ,A

and by it transmitted throughout the drum from end to end thereof. Such structure overcomes objectionsA andv diiiiculties attending structures sueltas hereinbefore mentioned in which driving power or torque is should be kept in circulation' to makeexit Y through the open heads at one or both ends of the drum. To assist or expedite such circulation l may employ within the drum a deflector plate or baffle 23, Fig. 1, suitably keyed to the shaft and serving to kdirect .they flow or current of dryingmedium, as` it leaves the perforations in the shaft, in op-` posite directions toward the heads of the drum, respectively, as approximately illusjtrated bythe arrows. To further assist such circulation, and particularly the discharge of moisture laden drying medium from the interior of the drum through the open drum heads,.1 may also employ one yor more fans.

1n Fig. 1 I have shown'two fans 24, 24,

keyed to the shaft 5 just inside of the drum heads 18, 18, each fan consisting ofl a khub and a plurality of blades radiating therefrom. i

The construction shownin Figs. 3 and 4 similar to that ofV Figs. 1 and 2, except in the following particulars: supply pipe 9 for the drying medium is bent at right angles at its upper end and makes a rotating` Ht within the end of tubular'shaft, 5. Fan blades 0r wings 25 are castintegral with or secured to spokesof the drum heads 16 and 17 instead of using vfan wheels secured to the shaft as in'Fig. 1i No baffle or deflector plate is shown in the structureof Figs. 3 and 4.

Pressure may be maintained upon the air or other drying medium inthe supply pipe 9, and valves may be employed in the pipe 9 leading vto each drier whereby the pressure at which such air` or drying medium enters the tubular shaft may be regulated, and the amount of air or drying medium furnished each drier also thus regulated. Thus, it may be found desirable as to some driers in a battery to furnish warm air in considerable quantity, and to other driers perhaps less air and of lower temperature. For example, lwhen the paper firstA comes from the size press it has beenfound desirable to dry slowly to give the size-opportunity to penetrate, and at this stage low temperature and less volume of air is believed to be preferable. Later on, when thel sine has fully set` hotter airv of greater Volume maybe employed withoutv injury tothe paper. However, the regulation would be The ,fixedy ionI . Maaate entirely in the hands of the operator in such a system, andA that has not been the case in the past.

In cases of very wide machines requiring correspondingly long slat driers it will be desirable to support the slats from thel shaft at one'or more intermediate points by one or more additional drum headsl similar to and spaced between the drum heads 16 andv 17 shown in the drawings. Also with very long driers, to gety the desired supplyy of drying medium it may be advantageous'to employ a tubular shaft of large interior diameter, or supply the drying medium at both ends of the shaftwhich in 'such case .could be of relatively small diameter.

.Vhat I claim is;

l. In combination, a rotatable Slat drier or drum for drying paper .having a tubular shaft or axle extending longitudinally therethrough and adapted to rotate in suitableV supporting bearings said shaft vhaving aper forated wall and being adapted to ser-.ve as a conduit for delivery of drying medium lcured to said shaft, spaced,peripheralA slats extending between and rigidly secured` to said drum heads, means for communicating to rotate in suitableY driving powerto said tubular shaft, Aand connections to the interior ofsaidtubular shaft for supplying drying medium from a 'f suitable source. Y y

3. In a rotatable slat drier or drum for drying paper., the combination-ofv a tubular y shaft or axleadap'tedto rotate infsuitable'` supporting bearings and to serve asv a con- 0.5-0,

duit for` delivery of drying medium withinthe drum through 'perfor-ations* in the wall of the shaft, two drum heads *rigidlyV sfe-v cured-to said shaft,peripheral slats extend;y

ing between and rigidly secured to said drum heads, means for communicating driving powerito said tubular shaft, connections to'one end ofsaid tubular shaft for supply@y ing drying medium. from a'suitabley source,

'and'fanblades attached to and rotating with Y said shaft and adaptedv-to'assist circulation 'vin-O within the drum.

4. In a rotatable slat drier or drumfor drying'paper, the combination of-a tubular shaft or axle adapted to rotate in -suitableAv supporting 'bearings and to serveyasu'a conj duitr fordeliveryA offdrying medium within the. drum through perforations', 'in the wall of the shaft, two drum headsrigidly secured to said shaft, peripheral slats extending -between and rigidly secured Ito said drum heads, means for communicatingv 4driving. power 'to said tubularshaft,rconnect1ons to one end of said tubular shaftnfor supplying l drying mediuinfrom a suitable source, and Y a. baffle or. deflector platesecured tothe shaft within the drum and adapted to deflect cir-` Y culation in yopposite directions .at opposite l sidesv thereof.

In testimony` whereof I have signed this i specification.

JoHN wARREN--`vEDDnn 

